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From: "colomar.6.4.3 at gmail dot com" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug c/101545] New: [[nodiscard]]: Incorrect warning when creating a function alias Date: Wed, 21 Jul 2021 07:06:58 +0000 [thread overview] Message-ID: <bug-101545-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101545 Bug ID: 101545 Summary: [[nodiscard]]: Incorrect warning when creating a function alias Product: gcc Version: 11.1.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c Assignee: unassigned at gcc dot gnu.org Reporter: colomar.6.4.3 at gmail dot com Target Milestone: --- The following code never discards that `42`, passing it to the caller of foobar() (in a different translation unit), and forcing it to read the value. The warnings about an ignored [[nodiscard]] are therefore incorrect. I put the contents of the header in the same source file just for simplicity. $ cat nodiscard.c [[nodiscard]] int foo(void); [[gnu::copy(foo)]] extern __typeof__(foo) bar; [[nodiscard]] int foobar(void); int foo(void) { return 42; } int foobar(void) { return bar(); /* This will return 42 */ } [[gnu::alias("foo")]] [[gnu::copy(foo)]] extern __typeof__(foo) bar; $ cc -Wall -Wextra -std=c2x -c nodiscard.c nodiscard.c:3:1: warning: 'nodiscard' attribute directive ignored [-Wattributes] 3 | [[gnu::copy(foo)]] extern __typeof__(foo) bar; | ^ nodiscard.c:18:1: warning: 'nodiscard' attribute directive ignored [-Wattributes] 18 | [[gnu::alias("foo")]] [[gnu::copy(foo)]] extern __typeof__(foo) bar; | ^
next reply other threads:[~2021-07-21 7:06 UTC|newest] Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-07-21 7:06 colomar.6.4.3 at gmail dot com [this message] 2021-07-21 7:07 ` [Bug c/101545] " colomar.6.4.3 at gmail dot com 2024-04-09 6:56 ` [Bug c/101545] copy attribute is not copying the C++11/C23 attributes correctly pinskia at gcc dot gnu.org
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